Quote Originally Posted by Whiteymorange View Post
I haven't seen this particular lens, but the Leitz projection lenses that appear to be similar are not Petzvals, they are triplets. 90mm may / should cover 6x6, but with projection lenses the question is what format they were intended to project. I have found some of that focal length that were intended for 35mm projection and they don't do a very good job with 6x6. Others do. Trial and error is your best guide, I'm afraid.
Thanks for feedback. I was able to look thru nikon F3 with this lens and get focus. So I will test this lens soon - when I get some kind of bellows or something to attach it on nikon body (since I still don't have SL66).